In the article Henry VIII: Henry the horrible (The Independent, 12 October 2003), Marcus Tanner wrote (emphasis added),
The man now remembered as the godfather of the Anglican church continued burning "heretics" to the end. England breathed a collective sigh of relief when this terrible bully breathed his last in Richmond Palace in 1547. Never again was England so near to being a state gripped by fear, a police state almost, as when Thomas Cromwell's spies were ferreting out "Papists" and "heretics", and hustling both to the stake. Never again was life at court quite so dangerous as it was under "bluff king Hal", when queens, bishops and statesmen as prominent as Sir Thomas More moved in single file up the royal hill of favour, and then down the other side to the block.
This made me wonder what the earliest depictions of a police state (or references to the existence of a police state) are on English-language fiction. (For the purpose of this question, only fiction counts, so letters, diaries, essays and pamphlets are excluded. It does not matter whether the police state was fictional or real.)
The Wikipedia article List of fictional police states lists several examples of police states in fiction. The oldest is We by Yevgeny Zamyatin, written 1920–1921, which is in Russian instead of English. The oldest example in English is Orwell's Nineteen Eighty-Four, published in 1949. The French Wikipedia article about police states does not list any older examples. Neither do the corresponding German and Spanish Wikipedia articles. Possibly the Wikipedia editors view the concept a bit too narrowly when looking for literary examples.
What could be the earliest reference to or depiction of a police state in English literature? For the purpose of this question, it is not necessary that the entire work focuses on life in a police state, nor that the term "police" is used explicitly.